# -*- coding:utf-8 -*-
# http://yongyuan.name/blog/pedestrian-detection-opencv.html
# import the necessary packages
from __future__ import print_function
from imutils.object_detection import non_max_suppression
from imutils import paths
import numpy as np
import argparse
import imutils
import cv2
class Camera_reader(object):

    def build_camera(self):
		# construct the argument parse and parse the arguments
		ap = argparse.ArgumentParser()
		ap.add_argument("-i", "--images", required=True, help="path to images directory")
		args = vars(ap.parse_args())

		# initialize the HOG descriptor/person detector
		hog = cv2.HOGDescriptor()
		hog.setSVMDetector(cv2.HOGDescriptor_getDefaultPeopleDetector())

		# loop over the image paths
		for imagePath in paths.list_images (args["images"]):
			# load the image and resize it to (1) reduce detection time
			# and (2) improve detection accuracy
			image = cv2.imread (imagePath)
			image = imutils.resize (image, width=min (400, image.shape[1]))
			orig = image.copy ()

			# detect people in the image
			(rects, weights) = hog.detectMultiScale (image, winStride=(4, 4), padding=(8, 8), scale=1.05)

			# draw the original bounding boxes
			for (x, y, w, h) in rects:
				cv2.rectangle (orig, (x, y), (x + w, y + h), (0, 0, 255), 2)

			# apply non-maxima suppression to the bounding boxes using a
			# fairly large overlap threshold to try to maintain overlapping
			# boxes that are still people
			rects = np.array ([[x, y, x + w, y + h] for (x, y, w, h) in rects])
			pick = non_max_suppression (rects, probs=None, overlapThresh=0.65)

			# draw the final bounding boxes
			for (xA, yA, xB, yB) in pick:
				cv2.rectangle (image, (xA, yA), (xB, yB), (0, 255, 0), 2)

			# show some information on the number of bounding boxes
			# filename = imagePath[imagePath.rfind("/") + 1:]
			# print("[INFO] {}: {} original boxes, {} after suppression".format(filename, len(rects), len(pick)))

			# show the output images
			cv2.imshow ("Before NMS", orig)
			cv2.imshow ("After NMS", image)
			cv2.waitKey (0)

if __name__ == '__main__':
	camera=Camera_reader()
	camera.build_camera()